A fellow activist calls the amnesty a ‘gift’ to improve bilateral relations.
The attack occurred after the group had gone to a prison to meet a fellow farmer jailed for protesting the seizure of his land.
Trade and security ties should be linked to progress on human rights, lawmakers and hearing witnesses say.
Truong Minh Tam hopes increased international scrutiny can improve the treatment of Vietnam's political prisoners.
Several people are taken away and detained by authorities in Hanoi and Tre Ben province.
Her family is concerned for her health three weeks into the fast.
She was planning a campaign calling for the release of political prisoners.